Table 2. Interrupted Time Series of Mortality and Readmissions at Patient- and Aggregate-Level.
| Outcome | Preintervention trend | Postmerger step change | Postmerger trend change | |||
|---|---|---|---|---|---|---|
| Patient-levela | OR (95% CI) | P value | OR 95% CI) | P value | OR (95% CI) | P value |
| Mortality | 0.995 (0.993 to 0.997) | <.001 | 1.48 (1.28 to 1.71) | <.001 | 0.97 (0.96 to 0.97) | <.001 |
| Readmission | 0.998 (0.997 to 0.999) | .001 | 0.85 (0.79 to 0.92) | <.001 | 1.00 (0.996 to 1.003) | .83 |
| Aggregative-level | Change (95% CI), % | P value | Change (95% CI), % | P value | Change (95% CI), % | P value |
| Mortality | −0.01 (−0.04 to 0.01) | .25 | 0.78 (0.12 to 1.44) | .03 | −0.17 (−0.24 to −0.09) | <.001 |
| Mortality excluding first mo | −0.02 (−0.04 to 0.01) | .18 | 0.80 (0.13 to 1.47) | .03 | −0.16 (−0.24 to −0.019) | <.001 |
| Readmission | −0.004 (−0.06 to 0.06) | .89 | −1.08 (−2.77 to 0.62) | .22 | −0.04 (−0.23 to 0.15) | .66 |
| Readmission excluding first mo | −0.06 (−0.09 to −0.03) | .001 | −0.69 (−1.50 to 0.13) | .11 | 0.01 (−0.08 to 0.10) | .81 |
Abbreviation: OR, odds ratio.
a
Adjusted for age, sex, diagnosis related group weight, Elixhauser comorbidities, payer, surgical vs medical diagnosis related group weight and season.